The evaluation of the wind-induced response of light and slender structures is strictly bound to damping modeling. While several papers exist dealing with damping of buildings, forecasting models concerning steel poles and tubular towers are almost totally lacking. In order to properly appreciate this quantity, an experimental full-scale activity has been undertaken whose project, execution and results are herein described. At present, four structures have been investigated providing, for each of them, the logarithmic damping decrement as a function of the motion amplitude. Preliminary results illustrated by this paper represent a starting point for the prosecution and the completion of a wider research aimed at formulating suitable damping mechanical models.